This invention relates to a pickup device for a disk drive device for reproducing a disk on which signals are optically or magnetically recorded or writing signals on a disk and, more particularly, to a technique capable of adjusting an optical axis of a pickup device reading or writing signals on a disk and also capable of improving shock resistance of the pickup device.
In the disk drive device, a pickup device including a pickup head is disposed opposite to a disk surface (i.e., a surface on which signals are recorded) and is supported slidably in the radial direction of the disk. The pickup head reads and writes signals on the disk surface while the pickup device slides in the radial direction of the disk. For ensuring accurate reading and writing of signals on the disk surface, the optical axis of the pickup head must constantly cross the disk surface. An adjusting device for this purpose is disclosed, for example, in Japanese Utility Model Publication No. Hei-5-4095. In this adjusting device, a pickup head is mounted on two adjusting bases which are slightly pivotable about two pivot axes in the radial direction of the disk and a direction crossing the radial direction. By turning screws mounted on pivoting end portions of the respective adjusting bases, these adjusting bases are slightly pivoted and the optical axis of the pickup is thereby adjusted. A coil spring biasing the respective adjusting bases in one pivoting direction is provided between the respective adjusting bases and the screws and shaking of the pickup head is prevented and shock to the pickup head is absorbed by the coil spring.
In the prior art adjusting device, however, the provision of the shake preventing and shock absorbing coil spring makes the device large (particularly in the thickness) and heavy with the result that the moving speed and response characteristic of the pickup device are reduced and the manufacturing cost increases due to increase in the number of component parts.
It is, therefore, an object of the invention to provide a pickup device for a disk drive device which is made compact and light and thereby the moving speed and response characteristic are improved and the manufacturing cost is reduced.